effect of rns in treatment-refractory tourette's syndrome

Conditions: Tourette Syndrome

Summary: the study is to investigate the effect of personalized responsive neurostimulation (rns) therapy guided by stereoelectroencephalography (seeg) in patients with treatment-resistant tourette's syndrome (tr-ts).

tourette's syndrome (ts) is a neurodevelopmental disorder characterized by repetitive, involuntary movements and vocalizations known as tics. it typically manifests in childhood and may persist into adulthood. the prevalence of ts varies globally, affecting approximately 1% of the population. there is a broad spectrum of symptom severity. treatment-refractory ts (tr-ts) refers to cases where standard therapeutic interventions, such as behavioural therapy and medications, have shown limited effectiveness. tr-ts prevalence is relatively lower but highlights the challenges in managing severe and persistent symptoms. in a comprehensive survey of diverse neuromodulation therapies, targeting specific nuclei with personalized responsive neurostimulation (rns) has the most potential for tr-ts with apparent symptoms. however, the rns case reports are limited and lack high-quality, evidence-based medical evidence. the stimulation targets of rns for patients with ts include gpi, amgpi, pvgpi, cm-spv-voi, cm-voi, and na-alic. while stereoelectroencephalography (seeg) brain mapping can help identify individualized effective targets and stimulation parameters. so, this cohort study focuses on the effectiveness of seeg-guided rns on tr-ts patients. another goal is to study the neuronal activity of the gpi, amgpi, pvgpi, cm-spv-voi, cm-voi, and na-alic, or other unreported nuclei targets, respectively. at the same time, some subjects are presented with a task involving an unexpected reward and different cognitive tasks. some participants will also be invited to join a related study that involves positron emission tomography (pet) scanning to determine how the stimulation changes activity in the brain. participation in the separate pet study is optional.

Eligibility criteria:
inclusion criteria: 1. aged 18-65; 2. able to provide written informed consent; 3. have a diagnosis of tourette's syndrome according to the statistical manual of mental disorders-fourth edition-text revised (dsm-iv-tr) criteria and confirmed by the mini-international neuropsychiatric interview chinese version 5.0; 4. with a ygtss of at least 35 for at least 12 months before surgery, while ygtss- total motor≥15; 5. must have failed conventional medical treatment at adequate therapeutic doses of three classes of medication lasting for at least three months; 6. must not be suitable for behavioural intervention or that this intervention is inappropriate or unsuccessful; 7. have been on stable comorbid conditions without suicidal ideation for at least six months. exclusion criteria: 1. presence of other psychotic disorders; 2. have a treatment history that includes electroconvulsive therapy (ect), modified electroconvulsive therapy (mect), transcranial direct current stimulation (tdcs), transcranial alternating current stimulation (tacs), dbs, and transcranial magnetic stimulation (tms); 3. presents a suicide risk (defined as a hamd-17 score of ≥3 on suicide-related items); 4. experience difficulty in effectively communicating with investigators; 5. with a history of traumatic brain injury (tbi); 6. with intracranial or cardiovascular stents; 7. substance abuse within the past six months; 8. unstable neurological or coagulation disorders; 9. women who are pregnant, lactating, or of childbearing potential who refuse the use of reliable contraception during the study; 10. have been involved in other clinical studies within three months before enrollment in this study; 11. any conditions considered by the study group.

Keywords: ts, rns